Wind energy has a very robust future ahead of it; currently it is the fastest growing sector of any renewable energy. It has the greatest potential to wean our society off or out of the fossil fuel era. World wide the total available wind potential, even excluding environmentally sensitive areas, is roughly five times current global electricity use suggests CANWEA. This is extremely significant and shows how the power of big industry keeps our leaders soaked in money so as not to commit to a drastic change over. Wind power has grown in excess of 30% per year for the past five years. Additionally the worlds total wind capacity has surpassed 39,000 MW and capacity is expected to exceed 95,000 MW by 2008 and 194,000 MW by 2013 (CANWEA). Lastly wind turbines are currently experiencing a 98% reliability factor and between a 25 and 30 year life span. This far out competes many conventional generation methods.
Wind energy is actually an indirect form of solar energy. The energy from
the sunlight interacting with Earth's atmosphere creates the conditions
that result in wind becoming a viable energy sources.
Wind is a source that can be used in many different locations. The only requirement
is a relatively constant wind. For the large scale commercially
generating turbines there are preferred locations where the local geography will
lead to better wind conditions.
Two main ones are:
1. Coastline
- along the shores of large bodies of water (lakes, seas or oceans) the flat body
of water means the wind can blow in a fairly steady manner from a fairly constant
direction.
2. Ridgeline
- turbines on land are preferentially places on a ridgeline. This means that
the wind is forced up the slope of the ridge or hill, resulting in increased
wind speed and therefore greater generation capability. On land turbines are
also situated in flatter regions so you get a similar effect as the coastline,
but the elevation does create a better situation.
Wind power has been used for centuries for many different purposes. The classic Dutch windmill has been in use in Holland to pump out the water, grind grains and turn saw blades. Another common design is the multi-vane, this was used primarily to pump water from wells. These two designs however have very low efficiencies capturing only between 7- 15% of the energy available in the wind.
Modern turbines use one of two designs, either horizontal or vertical axis. These designs have the blades set up so that they turn the shaft or rotor that will turn a turbine at different angles. The more efficient of the two is the horizontal design, but the blades need to be turned into the wind to generate electricity most effectively. The other design has a vertical rotor, and the blades look like an 'egg-beater' (sometimes referred to as the eggbeater design). Although this design is not as efficient, it does have the advantage that it can turn at the same effectiveness regardless of wind direction. This design is useful where the winds are strong, but shift constantly.
Both of these designs have a rotor (or shaft) that is turned by the blades of the wind turbine. The turning of this shaft is than converted to higher rpm with a gear box, and this then turns a generator. In the horizontal design, the generator is mounted on top of a post just behind the blades. In the vertical design, the generator is on the ground at the base of the shaft. The vertical design for this reason is also easier to maintain, and easier to install. It can usually also tolerate higher wind speeds.
In generating wind power, the maximum efficiency you can get from any turbine is 59%. This is a physical limitation. Modern turbines can now extract 30-40% of the energy (although constantly changing as the designs improve). The energy you can get out of the wind depends on two main factors, the diameter of the blades (in meters) and the velocity of the wind (m/s).
Turbines from an engineering stand point also have limits as to the wind speed they will work in. Below a certain wind speed, the blades won't turn, and above a certain speed, the winds would be too strong and damage or destroy the turbines. This depends on the design and type of the turbine.
One of the major areas of research is in blade design. Blades on turbines are not flat, but are shaped to maximize the capture of wind energy. Blades design will also be geared to different wind speeds. A blade is created to work most efficient around a particular speed. This means at different locations the best blade design will vary. On the horizontal design there are generally 2 or 3 blades, and on the vertical it is always a loop shape (2 blades).
Firstly it is necessary for a brief introduction to the situation here. Canada is quite far behind in terms of total installed capacity of wind energy. Canada is nineteenth in the world for total installed capacity Per capita, equal to 14.2 watts per person. As for the country with the highest total Wind energy capacity Germany takes the cake at over 16,000 megawatts. Ontario and Canada are seriously lacking, right now they are only contributing around 450 megawatts (Canadian total) by installing a few thousand megawatts of power this country could be back on par with what many other countries are generating. Ontario has the potential to increase the total capacity for Canada significantly, a big boost in construction could put this local within the top five in the world easily, and this is excluding the twelve other provinces and territories. CANWEA suggests that with 2002 technology there is over 3000 mega watts completely viable. Yet Ontario, the economic powerhouse of Canada, is not the leader of the country for installed capacity, contributing only a measly 15 mega watts of energy. The province that is really stepping up is Quebec, on October 4 2004 it was announced that 8 new projects are scheduled to be constructed with a total capacity of 990 mega watts. A second call for tenders is expected with another 1000 mega watts to be installed. Having such economic power Ontario should fully utilize this advantage and start to implement wind as a source of fuel free energy. Canadians need to appropriate themselves to a more European paradigm, specifically German, as this will ensure less of a reliance on fossil fuel energy.
Turbines can excel in provincial and federal economics, which are currently by no means close to their potential. If there is a backing of the Ontario government in renewable energies this will create an industry that has the potential to become quite large. Many large renewable energy focused companies from Europe, looking to expand have their eye on Canada. Most likely they were more intent on the US but their incentive policies are known to be sporadic and the government can flip flop at times. Canada should be capitalizing on this since there's really no infrastructure in this province for the development or construction of wind turbines. This problem needs to be rectified by the government partly by investing in programs designed to educate citizens as well as providing low interest loans to businesses and companies interested in tooling for the manufacture of necessary systems. Canada needs to have its government provide some good incentives for wind energy, as well as provide the commitment to install a large quantity of wind capacity. If this occurs it would look quite appealing for these companies to make a subsidiary bases in Canada. The benefits that would follow are likely to be quite important. The cost of turbines would decrease by about 3-5 percent due to the removal of shipping charges. On top of that with the addition of this infrastructure Ontario will create a variety of new jobs and the whole new industry. The total number of jobs created is debatable but estimates suggest about 12,700 by 2010 and upwards of 29,600 by 2020. The jobs would also be mostly located in rural areas where opportunities in the less developed areas of the province are essential. This of course will add to Canada's GDP and GNP. Another potential outcome Is that if Ontario is able to produce a large industry in wind energy it may become financially beneficial to sell carbon credits to other various countries in the world.
The benefits that have been discussed are mostly in relation to large scale generation, it's important to address some of the small scale benefits that will occur in a localized area. Many people are installing systems that are designed to power their cottage, house or farms. These are mostly intended to remove themselves from the grid so as to reduce the load and enable themselves to use green power. All of the same pollution benefits of the large scale systems are applicable to these small scale systems. Additionally due to their reduced size it is expected that there will be even less of an ecological impact on the surrounding areas. Another significant benefit will be that the owner will understand where the power is coming from, and conservation will likely begin to quickly become a major issue. Unlike today's large scale power grids where flicking on a switch results in light energy always, but where it comes from may be taken for granted.
Wind energy employs its distinct benefits and has the greatest potential of
all current renewable energies. Currently it is supplying 0.4% of the world's
total electrical Generation. This of course is not including any hydroelectric
installations future or past, as there is, and still can be a significant
contribution from this generation source.
For wind energy to become truly
useful and exploited it's Needs to be coupled with that of another technology.
Since the sun is usually shining quite bright on days that are not windy,
this is an ideal supplement. Ideally the match will be with solar energy but
panel efficiencies need to be made to capture and convert a much higher
amount of the available light. Alternatively there is the hydro electric
power that usually experiences lows in the winter when water is frozen and
precipitation falls as snow. Conveniently wind power is experiencing its
peak in the winter when the winds velocity is at its greatest. There is
also the possibility of wind coming together with the production of hydrogen
that could result in excess energy being stored as a pressurized liquid.
The hydrogen could then be used to fuel cars or other various hydrogen
devices as well as possibly being used to generate electrical energy through
a large scale fuel cell.
There are many barriers that wind turbines face I will quickly refute the common ones. They don't make a lot of noise and they don't kill thousands of birds, this has been proven many times and is a waste of time to argue. The argument that they destroy natural beauty is rubbish, since nobody seems to protest the installation of a hydro tower or a telecommunication poles. And if it's slotted to be built on or near a shore line everybody will complain saying that it is destroying the environment. Yet nobody will protest the construction of a cottage or summer house on a shore line that will cause just as much if not more destruction. To rectify this problem educational and informational sessions need to be held helping the public to understand why these systems need to be installed and why specific locations are selected.
This is a significant concern as many countries have no existing accurate wind maps. Without these maps it is extremely difficult for companies or citizens to determine if there is any potential for the installation of a turbine. They are mainly needed in the preliminary hunt for the best feasible location.
This is an extremely important factor that is not calculated (realistically not included) as it should be. The best thing that renewable have going for them is that they don't pollute the environment, the problem is that this very important factor is not even taken into account. Traditional generation requires that a fuel be consumed in some way to produce heat that is then converted via steam to a turbine that produces electrical energy. The byproduct of creating this heat is a pollution of some form, this pollution then causes sickness, property damage, premature death, ecosystem destruction, and climate change, among many other effects. Ray Darby Reiterates this by saying "These costs (externalities) are important in planning our energy use over the long term, because ignoring them leaves society open to the full range of side-effects associated with fossil fuel usage, the impacts of which we are just beginning to understand". The difficulty is that it can be hard to estimate the cost of these externalities. A comprehensive reworking of conventional power generation should be conducted and the true costs applied to these systems. This would remove the false pretense that coal or nuclear generated energy is cheap. Not only that but renewables, specifically wind energy would become so much more cost effective, considering it is able to compete now with no externalities accounted for.